Cleaning for COVID-19: Mixing products can create toxic gases

As COVID-19 spreads, health officials recommend residents take a number of precautions to protect themselves including practicing social distancing, proper handwashing and regular disinfecting of high-touch surfaces.

But some chemicals shouldn’t be mixed while cleaning.

There is a wide selection of household cleaning products on the market but many of them can be dangerous if not used correctly – if used in the wrong concentrations or mixed with other chemicals, a WorkSafeBC spokesperson explained.

For example, according to WorkSafeBC, isopropyl alcohol – an ingredient in many hand sanitizers and often used in cleaning – is flammable, can irritate the skin and eyes and is poisonous if consumed.

Bleach is commonly used in cleaning and disinfecting but if mixed with household ammonia products or acidic cleaners, it can create toxic gases. Some concentrated bleaches and acids can also burn the skin and eyes.

The best way to find out how to safely use a product is to read the product label and the safety data sheet that can often be found online, said Deputy Chief Dan Wood of the Saanich Fire Department. He advises against mixing any cleaning products as the outcome can be hazardous.

“We’re not all chemists, so keep it simple,” Wood said.

He added that antibacterials won’t be effective against COVID-19 as it’s a virus, not a bacteria. Instead, he suggests following the B.C. Centre for Disease Control (CDC) guide for an effective virucide: five tablespoons of bleach per gallon of water or four teaspoons bleach per quart of water.

According to the B.C. CDC website, household bleach is “effective against coronaviruses when properly diluted” as long as it’s not expired. Solutions with at least 70 per cent alcohol or most common Environmental Protection Agency-registered household disinfectants are also said to be effective against the virus.

In the event of an emergency involving a hazardous gas, Wood says to evacuate the area and call 911. The local fire department will have the proper safety equipment to go in and clean up, he added.

The Occupational Health and Safety Regulation and Workers Compensation Act also still applies to anyone working from home and WorkSafeBC recommends checking with a supervisor before using a chemical.